The present invention relates to a cap for hermetically closing a receptacle having a retention flange.
Traditional caps are made by molding and generally comprise a lid surmounting a lateral skirt which is provided, in a bottom portion, with means for snap-fastening beneath said flange, and in a top portion, with a removable tamperproofing strip occupying a fraction of the periphery of the skirt where it provides a temporary connection with the lid, and also providing a hinge in its complementary fraction.
However, with such caps, the lid does not remain in its fully-open position.
The plastics material used, in particular for making the hinge, possesses shape memory which has a tendency to return the lid towards the position it originally had on leaving the mold, which corresponds to the lid being closed.
Thus, after the tamperproofing strip has been removed, the equilibrium position of the lid corresponds to a partially-open position, which interferes with dispensing the content.
An object of the present invention is to resolve this technical problem in satisfactory manner.
According to the invention, this object is achieved by means of a cap characterized in that said lid carries a locking tab whose free end is provided with a retractable catch suitable for coming into abutment against the flange of the receptacle in the fully-open position.
According to an advantageous characteristic, said hinge comprises two bridges leaving a slot between them into which said locking tab extends.
Preferably, each of the bridges has a cavity defining a preferred zone for elastic deformation to enable the lid to be pivoted.
In a specific variant, said cavity is bordered laterally by two reinforcing ribs.
According to another characteristic, said catch is situated below the level of said cavity in the closed position of the lid.
According to yet another characteristic, said catch extends radially outwards in the closed position of the lid.
According to another variant, said catch has a chamfered outside side face for guiding the tab in contact with said flange.
According to a particular characteristic, said catch has a hook-forming trapezoidal cross-section.
Preferably, said locking tab is provided with a stiffener element bearing against its inner face to prevent it from bending inwards.
According to yet another variant, one of the ends of the tamperproofing strip is provided with a tongue.
Preferably, said tongue is received in a corresponding cutout of the lateral skirt.
In particular variants, said means for snap-fastening the skirt beneath the flange are constituted by a partially peripheral internal bead, while the bottom edge of said skirt comes into abutment against a bottom shoulder on the neck of the receptacle.
Furthermore, provision is made for said lateral skirt to be connected to the lid vertically in register with its peripheral edge in such a manner as to define a cylindrical envelope prior to snap-fastening on the receptacle.
Furthermore, the cap can further comprise a cylindrical sleeve secured to the bottom face of said lid and designed to be inserted inside the receptacle to come into leakproof contact with its top inside wall.
Advantageously, the peripheral edge of the lid is provided with a cutout in its zone diametrically opposite from the hinge.
The cap of the invention provides a stable fully-open position making it easy to dispense the content under all circumstances. Furthermore, the lid can be passed from the closed position to the fully-open position without any significant effort.
Finally, the cap of the invention is particularly simple and thus easy to make, making it possible to provide a fully functional assembly at an economic cost price.